Prefabricated and attached interconnect structure

ABSTRACT

A interconnect assembly features a prefabricated interconnect structure metallurgically bonded to a terminal of a larger structure. Fabrication of the interconnect structure&#39;s independently and separate from the larger structure enables the use of economic mass fabrication techniques that are well-known for miniature scale sheet metal parts. During fabrication, positioning and attachment, each interconnect structure is combined with and/or held in a carrier structure from which it is separated after attachment to the terminal. The interconnect structure is configured such that an attachment tool may be brought into close proximity to the attachment interface between the interconnect structure and the terminal for a short and direct transmission of bonding energy onto the attachment interface. The attachment interface provides for an electrically conductive and a bending stress opposing mechanical connection between the interconnect structure and the terminal. The interconnect assembly is preferably part of a probe apparatus.

RELATED APPLICATION

This application is a division of application Ser. No. 10/429,275, filedMay 1, 2003 now U.S. Pat. No. 6,965,245.

FIELD OF INVENTION

The present invention relates to interconnect structures forconductively contacting terminals. Particularly, the present inventionrelates to interconnect structures of a probe apparatus for testingsemiconductor devices.

BACKGROUND OF INVENTION

A conventional probe apparatus for testing semiconductor devicesincludes a number of interconnect structures for temporarily contactingtest terminals of the tested device. As the semiconductor technologyadvances, the tested devices become increasingly smaller while thenumber of simultaneously accessed terminals continues to increase. Atthe same time, commercial competition forces the industry to providesemiconductor testing at ever decreasing cost. To meet these demands,there exists a need for further improvement of probe apparatus.

A crucial component in a probe apparatus are the interconnect structuresthat are tightly arrayed within a probe apparatus. The interconnectstructures are configured for a reliable electrical contacting during ahigh number of test cycles. With advancement of semiconductors,interconnect structures become increasingly smaller and tighter arrayed.

Interconnect structures need to meet several functional criteria.Firstly, they need to be sufficiently flexible and resilient tocompensate for positioning discrepancies of test terminals. Secondly,the interconnect structures needs to scratch along the terminal'ssurface to remove any eventual insulating oxides and films prior toestablishing a conductive contact to the test terminals. This scratchingalso known in the art as scribing is accomplished by endowing theinterconnect structure with an elastic deformation characteristic thatresults in a relative motion of the interconnect's end along the testterminal's surface during an initial positioning. Thirdly, theinterconnect structures must be simple in shape and configuration to becost effectively fabricated in high numbers. Fourthly, the interconnectstructures need to be configured for a cost effective assembly in everincreasing numbers and tighter spacing.

In the prior art, two main designs for interconnect structures have beenimplemented to address the needs stated above. According to a firstdesign interconnect structures are fabricated as well-known bucklingbeams made of wire having a round and/or rectangular cross section.Buckling beams are oriented in a certain manner with respect to thetested terminals such that they buckle upon initial contact with thetest terminals. The resilient buckling of the beams provides forsuspension and scribing. Unfortunately, the buckling beams need to beheld at both ends with sufficient lateral space to permit buckling inthe middle of the buckling beams. This results in a relative complicateand cost intensive assembly.

In a second design concept, the interconnect structures are fabricatedas spring like features directly on a face of a larger structure of theprobe apparatus with which they are rigidly connected. Such largerstructure may include a well-known space transformer and/or a well-knownprinted circuit board [PCB] transformer. During the contacting with thetest terminal, the resilient deflection of the interconnect structuresis opposed by the larger structure on which the interconnect structuresare fabricated and with which they are rigidly connected.

The advantage of the second design concept is that the interconnectstructures need not be held on both ends as is required for the bucklingbeam probes. Unfortunately, the effort for fabricating spring likeinterconnect structures directly on the face of a larger structure isrelatively high. This is, because for a required contact force betweenthe interconnect structure and the test terminal, the spring typeinterconnect needs to have a structural strength that is significantlyhigher than that of a buckling beam. Also, since the deflection of eachspring like structure is opposed by the larger structure, each interfacebetween the two of them may be exposed to high stresses. As a result,the interface may need additional structural support. In the prior art,complicated fabrication steps are performed for fabricating spring likeinterconnect structures. Such fabrication steps include multiple layerdepositions and multiple layer shaping operations.

In the prior art, several problems associated with the fabrication ofsmall scale interconnect structures directly on the face of a largerstructure remain unresolved. One problem is to position and transportthe miniature structure during its fabrication. A second problem is toprecisely position an eventually pre-fabricated structure in its finalassembly position on a larger structure. A third problem is to attachthe eventually pre-fabricated structure in its final assembly position.The attachment is particularly problematic, where stresses are at amaximum in the attachment interface. The present invention addressesthese problems.

SUMMARY

An interconnect assembly combines prefabricated interconnect structuresthat are attached on terminals of a larger structure. The interconnectassembly is preferably part of a probe apparatus for testingsemiconductor devices.

The interconnect structures are prefabricated preferably from sheetmetal. The interconnect structures feature an attachment face with whichthey are attached to the terminals. The attachment face is part of abase, which also features an access face in close proximity andsubstantially opposing the attachment face.

The attachment is accomplished by a separate attachment tool that isbrought into contact with the access face through which a bonding energyis excerpted onto the base. The bonding energy is transmitted throughthe base towards the interface between attachment face and terminal. Asa result of the bonding energy, a metallurgical bonding takes placebetween the terminal and the attachment face. Bonding energy may beexcerpted in the well-known forms of thermal, electrical and/ormechanical energy. The metallurgical bonding includes soldering, brazingor welding.

Laterally protruding from the base is a suspension element with acontacting end on its distal end. The contacting end is configured foran eventual removing of an eventual oxide layer on top of the contactterminal—well-known as scribing. The contacting end is also configuredfor establishing a conductive contact with the contact terminal whilethe contacting end is forced against the contact terminal by a springforce of the suspension element.

The suspension element has a predetermined bending characteristic, whichprovides for the spring force and the scribing movement on a contactterminal during initial positioning movement of the interconnectassembly relative to the contact terminal.

During initial fabrication of the interconnect structure prior andduring its attachment to the larger structure's terminal, theinterconnect structure is combined and held in a carrier structure. Thecarrier structure and the interconnect structures are preferably ofmonolithic sheet metal. Once the attachment is completed, theinterconnect structure is separated from the carrier structure in awell-known fashion.

Various techniques may be utilized for fabricating the interconnectstructures. Such fabrication techniques may include, photolithographicetching, stamping, bending, forging, plating, laser machining, electricdischarge machining, electron beam machining, surface treating, andheat-treating. The interconnect structures may be arranged on thecarrier structure for a multiple simultaneous attachment or for asequential attachment to a number of attachment terminals.

The attachment interface between terminal and attachment face may beconfigured substantially independently from other dimensional constrainslike, for example, the suspension element's shape and/or the suspensionelements bending characteristic. This is particularly advantageous forconfigurations of the interconnect structure in which the spring forceresults in a high bending momentum within the attachment interface.

The suspension element may be configured to provide the spring forcewith substantially constant internal stress over its length. In suchconfiguration and for a required spring force and suspension elementmaterial, a maximum deflection is provided with a minimum of suspensionelement length.

The suspension element may be further shaped in a backwards-loopingfashion such that the contacting end and the attachment interface aresubstantially centered with respect to the spatial orientation of thespring force. In that fashion, bending momentum in the attachment facemay be substantially eliminated.

The attachment terminals serve firstly to transmit electrical signalsfrom conductive leads onto the interconnect structure. The attachmentterminals serve secondly to transmit force and bending momentum thateventually result from the spring force onto the larger structure. Forthe second reason, the terminals may be embedded in the larger structurefor an increased structural interlocking between the larger structureand the attachment terminal. The increased structural interlocking mayreduce an eventual risk of delimitation between the attachment terminaland the larger structure.

The larger structure may be a well-known space transformer or awell-known printed circuit board [PCB] transformer of the probeapparatus. Interconnect structures may be also attached in differentsizes and on opposing faces of a single space transformer.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a perspective view of a first embodiment interconnectassembly with a portion of a larger structure.

FIG. 2 illustrates the interconnect assembly of FIG. 1 in perspectivecut view.

FIG. 3 depicts a perspective view of an extended portion of the largerstructure in a first configuration.

FIG. 4 shows a portion of a first carrier structure positioned on top ofthe larger structure of FIG. 3 for attachment of the interconnectstructures held within the first carrier structure.

FIG. 5 illustrates the first carrier structure and larger structure ofFIG. 3 during a fabrication step in which a first number of interconnectstructures are attached to the carrier structure.

FIG. 6 depicts the first carrier structure and larger structure of FIG.3 during a fabrication step in which the first number of interconnectstructures are cut off the carrier structure while a second number ofinterconnect structures is attached to the carrier structure.

FIG. 7 shows the larger structure of FIG. 3 populated with interconnectstructures of FIGS. 5 and 6 simultaneously attached to the terminals ofthe larger structure.

FIG. 8 illustrates an extended portion of the larger structure in asecond configuration partially populated with a number of interconnectstructures sequentially attached to some of the terminals of the largerstructure.

FIG. 9 depicts the larger structure of FIG. 8 with an additionalinterconnect structure held within a portion of a second carrierstructure. The additional interconnect structure is positioned with itsbase in the vicinity of an unpopulated terminal for a followingsequential attachment operation.

FIG. 10 shows the larger structure of FIG. 8 with the interconnectstructure of FIG. 9 being attached to the unpopulated terminal of FIG.9.

FIG. 11 illustrates the larger structure of FIG. 8 with the attachedinterconnect structure of FIG. 10 being cut off from the second carrierstructure.

FIG. 12 shows the larger structure of FIG. 8 populated with theadditional interconnect structure of FIG. 11.

FIG. 13 depicts a perspective view of a second embodiment interconnectassembly with a portion of a larger structure.

FIG. 14 illustrates a portion of a probe apparatus.

DETAILED DESCRIPTION

As shown in FIG. 1 and according to a first embodiment of the invention,an interconnect assembly 1 includes a prefabricated interconnectstructure 10 attached to a conductive terminal 22 accessible on a face21 of the larger structure 20. Prior to attachment, the interconnectstructure 10 is prefabricated with an attachment base 15, a suspensionelement 13 and a contacting end 12. The attachment base 15 has an accessface 18 and an attachment face 17 that substantially opposes the accessface 18.

Rigid connection between the interconnect structure 10 and theattachment terminal 22 is provided by metallurgical bonding in anattachment interface between the attachment face 17 and a terminal face23. Metallurgical bonding in context with the present invention includessoldering, brazing and welding. The metallurgical bonding provides aconnection that is electrically conductive and structurallysubstantially rigid opposing at least a bending stress resulting in theattachment interface from an operational spring force at the contactingend 12. The metallurgical bonding may be established along the entireattachment interface or within region of the attachment interface.

The attachment interface may be defined in conjunction with well-knownparticularities of well-known attachment techniques and/or inconjunction with the forces resulting in the interface from the springforce to minimize stress within the regions as may be appreciated byanyone skilled in the art. In the exemplary case of utilizing laserenergy as bonding energy for establishing a metallurgical bonding, theattachment interface may include a number of dot like weld pointsdistributed in a suitable fashion between an attachment face 17, 117(see FIG. 13) and a terminal face 22, 82 (see FIG. 8). In anotherexemplary case where sonic energy is utilized as bonding energy forestablishing a metallurgical bonding, the attachment interface mayinclude a friction weld area distributed between an attachment face 17,117 and a terminal face 22, 82 in accordance with well-knownparticularities of sonic friction welding.

The suspension element 13 protrudes from the attachment base 15 adjacentthe attachment face 17 and adjacent the access face 18 such that theattachment of the attachment face 17 to the terminal face 23 and anaccess to the access face 18 are substantially unimpeded. The suspensionelement 13 has a deformation characteristic resulting in a bendingmovement 143 in responds to a positioning movement 142 induced to thelarger structure 20 relative to a contacting terminal 151, 162 (see FIG.14) while the contacting end 12 is held in a fashion opposing thepositioning movement 142. The bending movement translates into awell-known scribing movement 144 along the contacting terminal's 151,162 surfaces and a spring force forcing the contacting end 12 towardsthe contacting terminals 151, 162.

The spring force in turn causes an internal bending stress along thesuspension element 13 as is well-known in the mechanical arts. Thesuspension element 13 may be configured to provide the spring force witha substantially constant internal bending stress along its lengthbetween the base 15 and the contacting end 12. In such configuration andfor a required spring force and suspension element material, a maximumdeflection is provided with a minimum length of the suspension element13. Constant internal stress may be accomplished by adjusting the crosssection of the suspension element 13 along the length of the suspensionelement 13 as it is well appreciated in the art.

The main purpose of the interconnect structure 10 is to establish aconductive contact between the attachment terminal 22 and a contactterminal 151, 162. For that purpose, the contacting end 12 is configuredfor an eventual removing of an oxide layer form the contact terminals151, 162 during the scribing. Configurations of the contacting end 12may include a sharp edge, a pointed edge, an inverted V-shapeterminating in a pointed edge, a tip protruding from a face, or thelike. The contacting end 12 may be specially coated, solution treatedand/or heat treated for an increased wear resistance and metal-to-metalelectrical contact performance.

The larger structure 20 extends substantially within a assembly plane 24with a number of terminal faces 23 being preferably parallel and inplane with the assembly plane 24 (see also FIG. 3). At this point it isnoted that in context with the present invention, the term “largerstructure” defines any structure having at least one attachment terminal22, 82 (see FIG. 8) and having an extension substantially larger thanthe extension of the attachment terminal 22, 82 within the attachmentplane 24, 84 (see FIG. 8). The interconnect structure 10 is shapedpreferably along a contour plane 11 that is preferably aboutperpendicular to the assembly plane 24. In the context of the presentinvention, the contour plane 11 is a plane perpendicular to the attachface 17 and parallel to the scribing movement 144. The suspensionelement 13 protrudes in an angle relative to the attachment face 17 suchthat sufficient clearance is maintained between the suspension element13 on one side and the larger structure 20 and eventually adjacentinterconnect structures 10 on the other side during operationalresilient deformation of the suspension element 13 and the contactingend 12.

The terminal 22 may be conductively connected to a conductive lead 27for communicating an electric signal towards and/or away from theinterconnect structure 10. The conductive lead 27 may propagate withinthe larger structure 10 or on its face 21. In case the terminal 22protrudes all through the larger structure 20, the conductive lead 27may also be connected to the terminal 22 on an opposite face (not shown)of the larger structure 20.

As shown in FIG. 2, the terminal 22 may be embedded in the largerstructure 20 for an increased structural interlocking between the largerstructure 20 and the attachment terminal 22. Forces and momentumeventually resulting from the spring force are thereby transmitted fromthe base 15 onto the larger structure 20 with a reduced risk ofwell-known delamitation between the terminal 22 and the larger structure20.

FIG. 3 depicts a perspective view of an extended portion of the largerstructure 20 in a first configuration in which a dependent terminalspacing 28 and 29 are defined by a fabrication spacing 31 and 32, whichwill be explained in the following under FIG. 4. There, a portion of afirst carrier structure 19 is positioned on top of the larger structure10 as depicted in FIG. 3. Each of a number of interconnect structures 10is connected to the first carrier structure 19 via a cutoff bridge 16.

The first carrier structure 19 may be positioned with respect to thelarger structure 10 in a well-known fashion. For example, well-knownreference holes (not shown) may be placed correspondingly in the largerstructure 20 and the first carrier structure 19 such that well-knownalignment pins (not shown) snuggly and perpendicularly protrudingthrough the reference holes may align the first carrier structure 19with respect to the larger structure 20. In aligned position, eachattachment face 17 is placed adjacent and at least partially overlappinga terminal face 23. Each interconnect structure 10 is fabricated andheld within the first carrier structure 19 such that each attachmentface 17 is substantially in plane with a fabrication plane 14 of thefirst carrier structure 19. Hence, all interconnect structures 10 withinthe first carrier structure 19 may be brought simultaneous intoattachment position by merely positioning the first carrier plate 19with respect to the larger structure 20. For that purpose, the terminalspacing 28, 29 is selected in correspondence with the fabricationspacing 31, 32. In attachment position, assembly plane 24 andfabrication plane 14 are substantially parallel and substantiallycoincident.

The fabrication spacing 31, 32 is defined to provide sufficientseparation for the fabrication steps of the individual interconnectstructures 10. Fabrication steps of the interconnect structures 10include a partial separation and contouring of an interconnect structureblank, shaping of the interconnect structure blank and eventualfinishing operations. The fabrication spacing 31, 32 is furtherinfluenced by a required minimum stiffness of the first carrierstructure 19. The minimum stiffness may be defined for handling thefirst carrier structure 19 between fabrication steps and/or forpositioning the first carrier structure 19 onto the larger structure 20.

Partial separation may be accomplished with well-known techniques suchas photolithographic etching, stamping, laser cutting, plasma cuttingand the like. Shaping may be accomplished by well-known techniques suchas bending, forging, deep-drawing and the like. Finishing operations mayinclude coating, surface finishing, contour finishing, solutiontreatment, and heat treatment. Fabrication steps may be performedsimultaneously and/or sequentially.

The simultaneously positioned interconnect structures 10 may besimultaneously attached by a number of attachment tools 50. In suchcase, the attachment tools 50 may be spaced apart in accordance with thespacing of the access faces 18 within the first carrier structure 19.Each attachment tool 50 is configured to excerpt a bonding energy viathe access face 18 through the base 15 onto the attachment face 17 andthe terminal face 23. The bonding energy is of well-known nature tocause a heating of and/or between the attachment face 17 and theterminal face 23 to a level, where metallurgical bonding in theinterface between attachment face 17 and the terminal face 23 occurs.Bonding energy may include thermal energy, electrical energy and/ormechanical energy. Correspondingly, the attachment tool 50 may be partof a soldering apparatus, a laser welding apparatus, an electricalwelding apparatus, or a friction welding apparatus. Soldering, bracingor welding may accomplish metallurgical bonding between the attachmentface 17 and the terminal face 23. Metallurgical bonding may be furtheraccomplished without use of an attachment tool like, for example withwell-known fabrication techniques in which the terminal faces 23 and theattachment faces 17 are immersed in a liquid solder bath.

Following the attachment operation, the interconnect structures 10 maybe separated from the first carrier structure 19. As illustrated in FIG.6, a number of cutoff tools 60 may simultaneously cut through a numberof cutoff bridges 16. Well-known electric pulse melting, laser cuttingand so forth may accomplish the cutoff operation. The cutoff operationis preferably performed in a fashion that avoids or minimizes debris.

Separation may be further accomplished by temporarily fully separatingthe interconnect structure 10 from the first carrier structure 19followed by press fitting the interconnect structure 10 back into afriction based fit within the first carrier structure 19. In thatfashion, the interconnect structure 10 may be finally separated from thefirst carrier structure 10 by merely pressing it out of its press fit.The attachment tool 50 may be utilized for pressing the interconnectstructure 10 out of its press fit.

As shown in FIG. 7, a final interconnect assembly 1 according to thefirst configuration features interconnect structures 10 simultaneouslyattached to the terminals 22 with a spacing substantially equal to thefabrication spacing 31, 32.

FIGS. 8–12 show a second configuration of the interconnect assembly 2and its fabrication steps in which the interconnect structures 10 aresequentially assembled with an assembly spacing 41, 42 that issubstantially independent from fabrication spacing 31, 32. According toFIG. 8, a larger structure 80 has a number of attachment terminals 82arrayed on the larger structure 80 with spacing 41, 42. A number ofinterconnect structures 10 are attached to the terminal faces 83. Theinterconnect assembly 2 is shown in FIG. 8 in an intermediatefabrication state to illustrate the differences to the interconnectassembly 1. A final interconnect assembly 2 may feature interconnectstructures 10 attached to each of the attachment terminals 82.

The sequential attachment is explained in the following for a singleinterconnect structure 10. FIG. 9 depicts a fabrication step in which aninterconnect structure 90 is brought with its attachment face 17 intoproximity of an unpopulated terminal face 83. The interconnect structure90 is held within a second carrier structure 90 such that thepositioning of the interconnect structure 90 is unimpeded by priorattached interconnect structures 10 that are already part of theinterconnect assembly 2. The fabrication position of the interconnectstructure 90 within the second carrier structure 99 is defined in afashion that takes into account the spatial limitation at the attachmentposition of the interconnect structure 90. This is an important fact forselecting the spacing 41, 42 and/or selecting an assembly orientation ofthe interconnect structures 10 independently from the fabricationspacing 31, 32 and independently from an eventual fabricationorientation of the interconnect structure 90 within the second carrierstructure 99.

As shown in FIG. 9, the fabrication position of the interconnectstructure 90 is selected such that the second carrier structure 99remains sufficiently above the interconnect structures 10 while theattachment face 17 is brought into attachment position. To accomplishthis, the cutoff bridge 16 holds the interconnect structure 90 at itscontacting tip 12. As it may be appreciated by anyone skilled in theart, the cutoff bridge 16 may be placed at any location suitable for6fabrication of the interconnect structure 10, 90 and for positioningthe attachment face 17 with respect to the terminal face 23, 83.

In a following step illustrated in FIG. 10, the interconnect structure90 is attached to the unpopulated terminal 83 by the attachment tool 50in a fashion similar as described for the interconnect assembly 1. Theattachment tool 50 may also operate to push onto the access face 18 suchthat an eventual gap remaining after initial attachment positioningbetween the attachment face 18 and the terminal face 83 is closed. Theresilience of the suspension element 13 may assist thereby to absorb forthe resulting offset between the base 15 and the carrier structure 99.

After attachment, the interconnect structure 90 is separated by thecutoff tool 60 in a fashion similar to that explained for theinterconnect assembly 1. In the case, where the attachment face 18 wasforced into contact with the terminal face 83 by the attachment tool 50,the internal stress of the suspension element 13 is released as soon asthe cutoff operation is completed. Consequently, the cutoff interconnectstructure 90 bounces back into its original fabrication shape as isdepicted in FIG. 12. For the purpose of visibility, the interconnectstructure 90 is hatched in FIG. 12.

Whereas in the first configuration, the interconnect structures 10 aresimultaneously attached, in the second configuration the interconnectstructures 10 are sequentially attached. The teachings separatelypresented for the interconnect assembly 1, 2 may be combined in waysthat are well appreciated by anyone skilled in the art. Hence, the scopeof the invention includes embodiments in which sequential and parallelattachment may be combined to optimize the fabrication process inconjunction with particularities of the interconnect assembly 1, 2. Forexample, an interconnect assembly 1, 2 may feature a number ofdistinctly oriented and grouped interconnect structures 10 forcontacting a single contact terminal 151, 162, with a number ofcontacting ends 12. In such a case, sequential attachment may be splitinto groups of equally oriented interconnect structures 10. A largerstructure 20, 80 may be consequently populated by a sequentialrepetition of simultaneous attachment of groups of equally orientedinterconnect structures 10.

FIG. 13 depicts another embodiment of an interconnect assembly, in whichan interconnect structure 110 has a backwards looping suspension element113 that positions the contacting end 112 substantially centrallytogether with the attachment face 117 in direction of the positioningmovement 142. In that fashion, the attachment interface is keptsubstantially free of bending stress regardless of the spring force.

FIG. 14 illustrates a portion of a probe apparatus 140 in testingposition after positioning movement 142 towards a tested circuit chip160. The larger structure 20/80 is a well-known space transformer withinterconnect structures 10 attached on top and bottom. The interconnectstructures 10 that are attached on the bottom contact the test terminals162 of the tested chip 160. The interconnect structures 10 attached onthe top of the space transformer 20/80 are in contact with terminals 151of a well-known printed circuit board [PCB] transformer 150.Nevertheless, interconnect structures 10 may also be attached to the PCBtransformer contacting terminals (not shown) on the space transformer20/80.

Carrier plates 19, 99 as well as interconnect structures 10, 100 arepreferably fabricated from sheet metal. The sheet metal is preferablymonolithic. In other embodiments, the raw material from which theinterconnect structures 10, 110 are fabricated is a sandwiched compoundmaterial including a number of layers specifically configured for theirfinal placement in one or more elements of the interconnect structure10, 110. Layers may be selectively removed in well-known fabricationtechniques.

The carrier structures 19, 99 are sacrificial and disposed of afterattachment of the interconnect structures 10, 90, 100 to the attachmentterminals 22, 82 and after completion of the cut off operation. Thecarrier structures 19, 99 may be configured as substantially finiteelements containing a certain number of interconnect structures 10, 90,100. The carrier structures 19, 99 may also be substantially infiniteelements configured as a band continuously forwarded as interconnectstructure(s) 10, 90, 100 are used up during the assembly procedure. Theterm “substantially finite” means in context with the present inventiona limited area extension selected primarily for a feasible handling of asingle carrier structure 19, 99 within and during the assembly processof the interconnect structures 10, 90, 100. The term “substantiallyinfinite” means in context with the present invention a band likeconfiguration in which the length of the band is limited primarily byfeasibility of handling outside the assembly process as is wellappreciated by anyone skilled in the art.

A first fabrication apparatus may prefabricate the interconnectstructures 10, 90, 100 in a continuous fashion as is well known forprogressive dies. Such fabrication apparatus may be combined with asecond fabrication apparatus for positioning and metallurgical bondingthe interconnect structures 10, 90, 100 as explained above. The secondfabrication apparatus may be configured in a way similar to a well-knowntape application bonding apparatus. For an infinite carrier structure,an interconnect assembly may be fabricated by merely providing a roll ofsheet metal band on which the interconnect structures 10, 90, 100 areprefabricated immediately prior their final assembly. The infinitecarrier structure progresses thereby through a number of prefabricationstages in a rate that corresponds to the rate with which theinterconnect structures 10, 90, 100 are attached to the attachmentterminals 22, 82.

Accordingly, the scope of the invention described in the specificationabove is set forth in the following claims and their legal equivalent:

1. A probe element structure processed to fabricate a portion of aninterconnect assembly, said probe element structure comprising: acarrier structure; and at least one interconnect structure comprising: afirst end configured to be conductively coupled to a conductive regionof a substrate, a second end configured for conductive contact with adevice to be tested, and an attachment portion configured to becontacted by an attachment tool for metallurgically bonding theinterconnect structure to the conductive region of the substrate,wherein the second end of the interconnect structure is connected to thecarrier structure via a cutoff element to allow the interconnectstructure to be separated from the carrier structure.
 2. The probeelement structure of claim 1 wherein the probe element structure isfabricated from a unitary piece of sheet metal.
 3. The probe elementstructure of claim 1, wherein the interconnect structure includes asuspension element extending between the first end and the second end,the suspension element being configured such that an internal bendingstress that occurs along a length of said suspension element resultingfrom a spring force being applied to said suspension element issubstantially equal along a length of said suspension element.
 4. Theprobe element structure of claim 1, wherein the probe element structureis fabricated from a unitary piece of conductive material.
 5. The probeelement structure of claim 1, wherein the interconnect structureincludes a suspension element extending between the first end and thesecond end, said suspension element being backwards looped.
 6. The probeelement structure of claim 1, wherein a number of said interconnectstructures are assembled and oriented in separate orientations withrespect to said carrier structure.
 7. The probe element structure ofclaim 1, wherein said carrier structure is substantially finite.
 8. Theprobe element structure of claim 1, wherein said carrier structure issubstantially infinite.
 9. The probe element structure of claim 1wherein the interconnect structure includes: I. an attachment base atthe first end, the attachment base having:
 1. an attachment face forconductive coupling to a conductive terminal of the substrate, and
 2. anaccess face included in the attachment portion, the access facesubstantially opposing said attachment face for accessing said base withthe attachment tool; II. a suspension element protruding from saidattachment base such that said attachment of said attachment face viathe attachment tool is substantially unimpeded by said suspensionelement; and III. a contacting end positioned at the second end, saidcontacting end being configured for establishing conductive contact witha contact terminal of the device to be tested while said contacting endis forced against the contact terminal.
 10. The probe element structureof claim 1 wherein a footprint of the probe element structure issubstantially identical to a footprint of the substrate, therebyfacilitating the alignment of the probe element structure and thesubstrate.
 11. The probe element structure of claim 1 wherein the probeelement structure includes a plurality of the interconnect structures,the interconnect structures configured to be probes of the interconnectassembly, the interconnect assembly being a probe card assembly.
 12. Theprobe element structure of claim 1 wherein the probe element structureis processed using photolithographic techniques to define a shape of theinterconnect structure.
 13. The probe element structure of claim 12wherein the probe element structure is further processed to bend theinterconnect structure to extend at least partially away from thecarrier structure.
 14. The probe element structure of claim 1 whereinthe probe element structure is provided through processing of aconductive sheet, the processing including removing predeterminedportions of the conductive sheet to define a shape of the interconnectstructure.
 15. The probe element structure of claim 14 wherein the probeelement structure is further processed to bend the interconnectstructure to extend, at least partially away from the carrier structure.16. The probe element structure of claim 1 wherein the probe elementstructure includes a plurality of the interconnect structures, each ofthe plurality of interconnect structures being aligned with acorresponding one of the conductive regions of the substrate when theprobe element structure is aligned with the substrate.
 17. The probeelement structure of claim 1 wherein the substrate is a spacetransformer.
 18. The probe element structure of claim 1 wherein theprobe element structure is a multi-layered structure.